How we change what others think, feel, believe and do
Principle: We want now what we may not be able to get in the future.
When things become less available, they become more desirable. If we have the choice of getting it now or only possibly getting it in future, then we choose getting it now.
This increase in desire and consequent acquisitive action happens even if we do not need the item now. It is the scarcity that drives our desire, not the utility of the item in question.
There is often a strong social element to scarcity. If it seems other people may get something that we could have now, we are even more tempted to get it.
A shop has a sale, with signs such as 'last few', 'limited availability' and 'special offer today only'.
A parent tells a child that refuses vegetables that if they do not want them, then their sibling, who likes vegetables, will be given them all.
A person selling a house points out a number of unique features that have been added to it. Even though they do not particularly like the features, many viewers end up thinking the house is more valuable than if the features were not there.
Scarcity works through anticipated regret, where we think about the future and see ourselves regretting having not taken a decision to act. In a present view, we fear not being able to get something in the future. When we think about the future, we not only anticipate events, we also experience the associated emotions. This present emotion then drives present decisions.
In prospect theory, we tend to value a gain that is certain more than a gain that is less than certain. The same effect is happening here as our need for certainty overrides rational thinking. Scarcity focuses more on loss than gain and so uses a similar principle.
We also anticipate social effects. When other people might get what we are contemplating getting now, we may fall into anticipated envy, where we imagine them having the item and us wishing we had it. Our consideration of status exacerbates us as we think that the person who has the item will be somehow superior. There is a doubling effect here in the gap between us having it, with the status that this gives us, and them having it, with both the loss of status to us and gain in status for them.
Scarcity can cause unwanted effects. For example a parent who forbids their children from doing things or only gives them small amounts of alcohol can make the child slyly seek greater amounts than if the parents were more open.
Scarcity works best when it is newly experienced. When people see the same thing in the sale on successive days, they become less inclined to buy it.
When it is hard to get something, we value it more when we get it. When information is harder to access, we are more likely to believe that it is correct. It is as if we need our efforts to acquire it to be repaid by its inherent value. The same effect happens when it is hard to join a group -- after joining we value being members far more than if it was easy to join.
Cialdini, R. (1984). Influence: The Psychology of Persuasion, New York: Quill
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